Manufacture of glass.



\ No. 805,139. PATENTED NOV. 2l, 1905. l H. K. HITCHCOCK.

MANUFAGTURE 0F GLASS.

APPLICATION FILED JUNE 13, 1904.

asuma-SHEET 1.

WITNESSES: v IN ENTOR No. 805,139. PATENTED NOV. 21, 1905. H. K. HITCHCOCK.

MANUFACTUREOF GLASS.

APPLICATION FILED JUNE 13, 1904.

2 SHEETS-SHEET 2.

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WITNESSES: Y l VENTOR4 M. Lamm K. LLM, @MA/4MM. CLfCg'd-QAnvs UNITED STATES PATENT oEfErCE.

HALBERT K. HITCHCOCK, `OF WALTON, PENNsYLvh'NImAssICNOR To HIMsELF AND CHARLES W. BROWN, TRUsTEEs, OF PITTSBURG,

PENNSYLVANIA.

MANUFACTUFKE OF GLASS.

Patented Nov. 21, 1905. I

Application led June 1S. 1904..l Serial No. 212.85%.

lTo all whom it may concern:

Beit known thatI, HALBERT K. HITCHCOCK, a citizen of the United States, residing at Walton, in the county of Allegheny and State of Pennsylvania, have invented or discovered certain new and useful Improvements in the Manufacture of Glass, of which improvements the following is a specification.

The invention described herein relates to certain improvements in the manufacture of g ass. v

It has heretofore been the practice in the manufacture of`glass to thoroughly mix together the several ingredients-6. g. thesilica, lime, and alkali-to form the batch and then subject them in a suitable pot or furnace to a fusing and refining temperature. On account of the great difference between the fusingpoints ofthe several ingredients of the batch and the temperature at which they unite to form glass there is always a great loss by volatilization of one or more of the less refractory ingredients. Hence such ingredients must be added in larger quantities to the batch than would be otherwise necessary.'

The object of the present invention is to 'bring the ingredients, the more refractory independently of the less refractory, to a condition of temperature where they will chemically act one upon the other as soon as mixed together. It is a further object of the invention to provide for the elimination of air or gas bubbles and also for the recovery of commercially valuable by-products, such as gases, evolved during the production of the glass. The invention is hereinafter more fully described and claimed. Y

In the accompanying drawings, forming a part of this specification, Figure 1 is a plan view of a furnace an'd connections adapted to the practice of my invention. Fig. 2 is a sectional elevation of the same, the plane of sec` tion being indicated by the line IIII, Fig. '1;- and Fig. 3 is a transverse section on a plane rindicated by the line III III, Fig. 1.

In the practice of my invention the silica or the silica and lime,'if glass having lime is' desired, are raised to a temperature at which there will be an elimination of impurities contained insuch material or materials and injurious to the desired product. ing-points of the silica and lime are above the temperature at which the contained impurities will be'volatilized and driven off, it is not necessary to raise the silica or silica and lime materially above such purifying temperature. As the melting-points of the lime and silica are so near together that there will not be any material volatilization of the less refractory if the two are mingled together and raised to the melting-point of the more refractory and as it is not necessary to raise the materials to the melting-point of the less refractory of the two, these materials may be mixed together in the desired proportions when making limeglass and then purified by high heating, as stated. After the silica or lime and silica have been purified the Huizing-alkali is added thereto, preferably in a fluid condition. If

rately purified, it is preferred to thoroughly mix them together before adding the iiuX. By the addition of the fluxing-alkalithe melting-point of the silica or the mixture silica and lime is lowered considerably below that of either the lime or silica or the silica and lime combined. In general the silica and lime and silica will while being purified be heated to such a temperature that on the addition of the fluXing-alkali the mass will pass immediately into a thoroughly fused or liquid condition, forming glass. On the `addition ofthe fluxing-alkali there will be a considerable evo? lution of gases which can be utilized, and proand storing such gases.

After the glass has been formed as stated the fluid-pressure on its surface is reduced, thereby relieving the tension in the air Or gas refractoryand chemically-inert cases 2, pref- -erably formed of carborundum, passing through the chamber and preferably in proxwhen lime and silica are used they are sepavision should therefore be made for collecting bubbles in the mass, permitting them to ex- As the meltgranulated carbon cores enveloped in highlyimity to the bottom thereof. 'llhesecasings are removably arranged in the chamber and are provided at their ends with detachable ter-A minals 3, to which are connected conductors 4:, leading to a suitable generator, said terminals contacting with the carbon cores. The silica or lime and silica are preferably charged into the hopper 5, which directs thematerial or materials to the troughs or tubes 6, having the conveyer-screws 7 arranged therein. suitable interposed mechanism by a motor 8. By this charging mechanism the. material or materials can be fed at any desired rate into the'chamber, where they 'are subjected to a purifying temperature which may be as high as the fusing temperature of one or both of said materials. The bottom of the chamber 1 is inclined so that the material or materials when purifiedwill flow under the partition 9 into the {inning-chamber 10. As the highly-heated silica or lime and silica enter the chamber 10 they come into contact with the fluid fiuxing-alkali--e g., salt cake or soda-ash or salt-and are caused to combine chemically therewith and with each other when lime and silica are used.

The alkali is placed in a hopper 11 and fed therefrom by screw conveyers 12 into the pot or receptacle 13, where it is reduced to a liquid or gaseous condition b v heat applied eX- ternally to the pot. The iiuid alkali flows from the pot into the distributing pipe or pipes 14, which are arranged on the bottom of the chamber 10 and provided with perforations so disposed asto effect a thorough distribution of the Huid flux through the silica or mingled silica and lime. The gases evolved or escaping during the iiuxing operation are conducted away by the pipe 19 to a place of storage, use, or treatment. After the glass has been formed by the addition of the iiux it is caused to pass over a dam 15, which is arranged under a hood or bell 16, so arranged that its edges will dip down into the glass on both sides of the diaphragm or dam 15. The hood or bell is provided with a neck 17, which is connected to a suitable eX- haust mechanism, whereby any desired vacuum may be maintained in the bell or hood. The dam is made of such a height that the glass will be forced over it by the greater pressure in the chamber 10, preferably in a comparathe bell or hood. ISufficient glass is ladled into chamber 16 to form and maintain a seal with the lower edge of. the bell or hood on' that side of the dam. By causing the exhaust mechanism to discharge into a suitable receptacle the gases contained in the bubbles may be recovered and utilized.

It will be understood that, while not neces- These con veyers are d riven th rough coarse sary, both the silica and: lime, whens both are used, may be highly heated before being mingled together, or either one mayhelquefied and the other added thereto r in a solid or liquid condition. Vlha all cases it is preferred that materialor materials employed f should be purified before the iiuxing stage, so as to avoid `maintaining the glass for any considerable length of time at a high or purifying temperature, for the reason that glass at such high temperature is an unstable compound and iseasily broken up by heat with the evolution of gases. -By the purification prior to iuxing the formation. olf gases except su'ch as are due to fluxing' imaveideda. By subjecting the glass to a partial vacmim afterthe iiuxing is completed:- the gas-bubbles consequent on such ilu-:ing are rapidly removed, and hence the glass needA be-.keptin a condition where it is liable to change-@hiya shortv time.

.l claim herein as my in-vfmtionf.-v

1. As an improvement in the art of making glass, the method described@ herein, which consists in heating the sil-ica to edect theelimi# nation of impurities and while in said condition adding a'iluXing-alkali. in iiuid con, dition, substantially as set forth.

2. As an improvement in the art of making glass, the method described herein, which consists in heating the lime andi silica and while said materia-laars heated adding afl'uxing-alkali in a fluid condition, substantially as set forth.

3. As an improvement inthe art of making glass, the method herein. described, which consists in heating the more' refractory materials to the temperature required.' for the less refractory to act upon them,` heating the less refractory ingredients, andy then-subjecting the more refractory materialswhile heated to the iiuxing action of the heated less refractory materials, substantially as set forth.

11. As an improvement in the art of making glass, the method herein described, which consists in heating the more refractory materials to the temperature required for 'uxing and forcing the less refractory material ingredients up through. the heated materials, substantially as set forth.

5. As an improvement in the art of making glass, the method herein described, which consists in heating the lime and silica, add-ing a fluxing-alkali in a fluid conditionl tosaid materials while in a fiuid condition, and subjecting the glass thus formed to a reduced surface-pressure, substantially as set forth..

6. As an improvement in the art of making glass, the method herein described which consists in heating the silica to effect the elimination of impurities, vaporiz'ing a iuxing-salt and. passing such vapor 'through the heated silica, substantially as set fort .y

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7. As an improvement in the art of making In testimony whereof I have hereunto set glass thal method hherein desieribed which collimy hand. sists in eating t e more re ractory materia s to the temperature required for uxing, vap- HALBERT K HITLHQOCK' 5 orizing a uXing-salt and forcing such vapor Witnesses:

through theheated materials, substantially as DARWIN S. WoLooT'r, set forth. F. E. GAITHER. 

